Selective serotonin reuptake inhibtor (SSRI) antidepressants may increase the likelihood that a user will suffer from a stroke or serious stomach bleeding events, according to a study published in the British Medical Journal. According to its lead author, the findings add to a growing body of evidence that some newer antidepressants, like SSRIs, may be associated with elevated risks of gastrointestinal bleeding and stroke.

Background: SSRI AntidepressantsSSRI antidepressants include drugs sold under the names Paxil, Prozac, Celexa, Lexapro, and Zoloft. SSRIs block the reabsorption (reuptake) of the neurotransmitter serotonin in the brain. It appears that altering the balance of serotonin helps brain cells send and receive chemical messages, which in turn boosts mood.

According to the British Medical Journal Study, over 255 million prescriptions for antidepressants are issued annually, and this number continues to increase. SSRIs and other new-generation antidepressants are generally preferred over older treatments such as tricyclic antidepressants or monoamine oxidase inhibitors on the basis of greater tolerability and safety

A growing body of research has linked these medications to birth defects when they are used by pregnant women, especially in the early months of pregnancy when many women don’t realize they are pregnant. Other SSRI antidepressant side effects include:

Nausea

Dry mouth

Headache

Diarrhea

Nervousness, agitation or restlessness

Reduced sexual desire or difficulty reaching orgasm

Inability to maintain an erection (erectile dysfunction)

Rash

Increased sweating

Weight gain

Drowsiness

Insomnia

The British Medical Journal StudyFor this study, researchers at Massachusetts General Hospital analyzed data from 36,000 patients with a diagnosis of major depression taking SSRIs as monotherapy, and the frequency of bleeding complications over a 19-year period. The study subjects were identified from among 3.1 million patients in a New England healthcare system. Patients in the study who took SSRIs were classified by relative affinity (low, moderate or high) of the drugs for the serotonin transporter during an exposure risk period for each patient. Patients who had multiple prescriptions and those on older antidepressants – tricyclic antidepressants or monoamine oxidase inhibitors – were excluded

The study found:

601 gastrointestinal bleeds were observed in the 21 462 subjects in the high-affinity group

333 gastrointestinal bleeds were reported among the 14 927 subjects in the lower affinity group

776 strokes were observed in the high-affinity group

434 strokes were seen in the lower affinity treatment group

The study authors concluded that use of antidepressants with high affinity for the serotonin transporter may confer modestly elevated risk for gastrointestinal and other bleeding complications. “It confirmed by further investigation, it may be possible to achieve these benefits while minimizing risk by selecting antidepressants with lesser affinity for serotonin transporter,” said Patience Gallagher, the study’s lead research and clinical research coordinator at Massachusetts General Hospital.